One side of my Philips ear buds stopped working, so it was time for a new pair (which was fine, because I didn't like them anyway)*. I decided on these mid-priced (US$60) Incase Capsule ear buds.
The sound is clean and well balanced, but the bass seems a little tight. Hopefully it will loosen up after a bit more use. On first listen though, I like them a lot.
It comes with 3 sizes of ear plugs, allowing for a comfortable fit with good sound isolation. However, I found the plugs pull off relatively easily (like when taking them out of my pocket), making them easy to lose if you're not careful.
***
Follow up:
After letting them wear in for a couple of months, the bass and overall dynamics do get better, producing a more natural sound. For the above average audio quality at this reasonable price point, these are a solid choice.
*You can read my review of the Philips here.